fix: session reconnect catch-up, always-on input, frozen session recovery (#524)

- WebSocketContext: emit 'websocket-reconnected' on onopen when it's a reconnect
  (hasConnectedRef tracks first-connect vs. subsequent reconnects).
- useChatRealtimeHandlers: handle 'websocket-reconnected' via onWebSocketReconnect
  callback; added to globalMessageTypes to bypass sessionId mismatch checks.
- ChatInterface: on reconnect, re-fetch JSONL session history so messages missed
  during iOS background are shown immediately. Also resets isLoading and
  canAbortSession so a dead/restarted session no longer freezes the UI forever.
- ChatComposer: remove disabled={isLoading} from textarea — users can always
  type regardless of processing state; submit button still prevents double-send.

Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

src/components/chat/hooks/useChatRealtimeHandlers.ts

@@ -48,6 +48,7 @@ interface UseChatRealtimeHandlersArgs {
   onSessionNotProcessing?: (sessionId?: string | null) => void;
   onReplaceTemporarySession?: (sessionId?: string | null) => void;
   onNavigateToSession?: (sessionId: string) => void;
+  onWebSocketReconnect?: () => void;
 }
 
 const appendStreamingChunk = (
@@ -113,6 +114,7 @@ export function useChatRealtimeHandlers({
   onSessionNotProcessing,
   onReplaceTemporarySession,
   onNavigateToSession,
+  onWebSocketReconnect,
 }: UseChatRealtimeHandlersArgs) {
   const lastProcessedMessageRef = useRef<LatestChatMessage | null>(null);
 
@@ -136,7 +138,7 @@ export function useChatRealtimeHandlers({
         : null;
     const messageType = String(latestMessage.type);
 
-    const globalMessageTypes = ['projects_updated', 'taskmaster-project-updated', 'session-created'];
+    const globalMessageTypes = ['projects_updated', 'taskmaster-project-updated', 'session-created', 'websocket-reconnected'];
     const isGlobalMessage = globalMessageTypes.includes(messageType);
     const lifecycleMessageTypes = new Set([
       'claude-complete',
@@ -300,6 +302,11 @@ export function useChatRealtimeHandlers({
         }
         break;
 
+      case 'websocket-reconnected':
+        // WebSocket dropped and reconnected — re-fetch session history to catch up on missed messages
+        onWebSocketReconnect?.();
+        break;
+
       case 'token-budget':
         if (latestMessage.data) {
           setTokenBudget(latestMessage.data);

src/components/chat/view/ChatInterface.tsx

@@ -109,6 +109,7 @@ function ChatInterface({
     scrollToBottom,
     scrollToBottomAndReset,
     handleScroll,
+    loadSessionMessages,
   } = useChatSessionState({
     selectedProject,
     selectedSession,
@@ -197,6 +198,23 @@ function ChatInterface({
     setPendingPermissionRequests,
   });
 
+  // On WebSocket reconnect, re-fetch the current session's messages from JSONL so missed
+  // streaming events (e.g. from long tool calls while iOS had the tab backgrounded) are shown.
+  // Also reset isLoading — if the server restarted or the session died mid-stream, the client
+  // would be stuck in "Processing..." forever without this reset.
+  const handleWebSocketReconnect = useCallback(async () => {
+    if (!selectedProject || !selectedSession) return;
+    const provider = (localStorage.getItem('selected-provider') as any) || 'claude';
+    const messages = await loadSessionMessages(selectedProject.name, selectedSession.id, false, provider);
+    if (messages && messages.length > 0) {
+      setChatMessages(messages);
+    }
+    // Reset loading state — if the session is still active, new WebSocket messages will
+    // set it back to true. If it died, this clears the permanent frozen state.
+    setIsLoading(false);
+    setCanAbortSession(false);
+  }, [selectedProject, selectedSession, loadSessionMessages, setChatMessages, setIsLoading, setCanAbortSession]);
+
   useChatRealtimeHandlers({
     latestMessage,
     provider,
@@ -219,6 +237,7 @@ function ChatInterface({
     onSessionNotProcessing,
     onReplaceTemporarySession,
     onNavigateToSession,
+    onWebSocketReconnect: handleWebSocketReconnect,
   });
 
   useEffect(() => {

src/components/chat/view/subcomponents/ChatComposer.tsx

@@ -301,8 +301,7 @@ export default function ChatComposer({
               onBlur={() => onInputFocusChange?.(false)}
               onInput={onTextareaInput}
               placeholder={placeholder}
-              disabled={isLoading}
-              className="chat-input-placeholder block max-h-[40vh] min-h-[50px] w-full resize-none overflow-y-auto rounded-2xl bg-transparent py-1.5 pl-12 pr-20 text-base leading-6 text-foreground placeholder-muted-foreground/50 transition-all duration-200 focus:outline-none disabled:opacity-50 sm:max-h-[300px] sm:min-h-[80px] sm:py-4 sm:pr-40"
+              className="chat-input-placeholder block max-h-[40vh] min-h-[50px] w-full resize-none overflow-y-auto rounded-2xl bg-transparent py-1.5 pl-12 pr-20 text-base leading-6 text-foreground placeholder-muted-foreground/50 transition-all duration-200 focus:outline-none sm:max-h-[300px] sm:min-h-[80px] sm:py-4 sm:pr-40"
               style={{ height: '50px' }}
             />
 

src/contexts/WebSocketContext.tsx

@@ -29,6 +29,7 @@ const buildWebSocketUrl = (token: string | null) => {
 const useWebSocketProviderState = (): WebSocketContextType => {
   const wsRef = useRef<WebSocket | null>(null);
   const unmountedRef = useRef(false); // Track if component is unmounted
+  const hasConnectedRef = useRef(false); // Track if we've ever connected (to detect reconnects)
   const [latestMessage, setLatestMessage] = useState<any>(null);
   const [isConnected, setIsConnected] = useState(false);
   const reconnectTimeoutRef = useRef<NodeJS.Timeout | null>(null);
@@ -61,6 +62,11 @@ const useWebSocketProviderState = (): WebSocketContextType => {
       websocket.onopen = () => {
         setIsConnected(true);
         wsRef.current = websocket;
+        if (hasConnectedRef.current) {
+          // This is a reconnect — signal so components can catch up on missed messages
+          setLatestMessage({ type: 'websocket-reconnected', timestamp: Date.now() });
+        }
+        hasConnectedRef.current = true;
       };
 
       websocket.onmessage = (event) => {